I have no idea what I would have done. I think it makes you sound like a know-it-all if you had, but really awkward letting her continue to think something false. I think you did the right thing, because what’s it really worth to point this out to people? If I had to hazard a guess, she didn’t read it in some book. This might have been some story her parents used in order to pass [name]Nora[/name] off as a form of [name]Mary[/name] to relatives who pressured for it, and grew up believing it. I am torn as to whether people should continue to believe these kinds of things (it’s not as bad as not knowing you’re adopted, for instance), or if it’s none of your business. Maybe she confused something about it when she was young and not her parents’ doing at all. I can’t fathom any modern baby name book would erroneously publish [name]Nora[/name] as a form of [name]Mary[/name], so hope that she eventually discovers it on her own… I guess. Or not.
I have addressed a similar situation without coming off too harshly, I think:
I just met someone with a nickname. I had thought he was Italian (because of his nickname), but he turns out to be Greek. I ask him what then it could be short for, as it’s primarily Italian and I know what it’s short for in Italian, and he tells me a great Greek name, somewhat hardcore and magnificent. [I’m sorry, I don’t want to say too much about what his name actually is, so I hope this suffices.] I think, wow, neat! But I also pointed out then, why isn’t he called essentially the same nickname with a different first letter, even though that’s mostly Italian too. It would at least have the same letters as his full name and not be kind of “off” by that one letter - it bugs me a little!
Next time I saw him, I ask him to write his name down for me but he said for me to write it. He says the nickname is what’s on his birth certificate. (kind of a downer for me). Then he tells me the big name starts with a C. Hello, my friend, your parents just came here from Greece (before he was born), gave you an Italian nickname for a name, and spell your “real” name with a C instead of a K? I mean, I told him all of this, because of course I looked it up and wanted to ask him about it again. It’s not really a huge deal, I guess, but the story didn’t turn out like I’d hoped, and as it went, I don’t think I damaged anything in knowing things he should know and pointing it out to him. And furthermore, if they were intent on naming him the C name that should start with a K, he should have a different nickname for his American birth certificate name, it’s a very common nickname for Greeks with that name when they aren’t in Greece anymore.
I think some real sleuths will figure out exactly what I’m saying. I just don’t want to betray anything by writing down the story. Also, he loves his name. I’m getting used to it and try not to address it anymore, as I still want it to be the K name on the paper. Am I really sounding shallow? It’s not a deal-breaker or anything. [name]Just[/name] name nerd disappointment!